80 THE AMERICAN MIDLAND NATURALIST. 
Erysimum inconspicuum (§. Wats.) Mac.M. 
Prairie. Common. June 20 (18). 
Barbarea barbarea (1,.) Mac.M. WINTER CRESS. 
Collected by C. H. Waldron in 1gro. 
Brassica nigra (1,.) Koch. BLACK MUSTARD. 
Roadsides. Rare. 
Brassica juncea (1,.) Cosson. INDIAN MUSTARD. 
Roadsides and fields. Frequent. June 15 (scant data). 
Brassica arvensis (1,.) B. S. P. *COMMON MUSTARD. 
Fields and roadsides. Common. May -207(321)2 
Brassica campestris \. 
Roadsides. Occasional. 
Erucastrum pollichi Schimp. & Spenn. *DOG MUSTARD. 
Frequent along the railroad tracks and occasional along streets. 
June 15. This common name which is proposed is a contraction 
of one used in a European manual. The plants flower vigorously 
in the fall until after the first frost, frequently into November. 
Eruca eruca (1,.) Britton. GARDEN ROCKET. 
Collected by L. R. Waldron in 1902, by Bergman in 1912. 
Draba nemorosa \. YELLOW WHITLOW GRASS 
Fields. Occasional. Only one early record—Apr. 24, 1910. 
Arabis hirsuta (1,.) Scop. HAIRY ROCK CRESS. 
Common in prairie, occasional in fields. June 20. 
Conringia orientdlis (I,.) Dumort. HARE’S-EAR MUSTARD. 
Roadsides and fields. Occasional. June 5 (4). Most commonly 
known in this state as ‘‘Black Mustard.”’ 
Polygonum amphibium \. 
In water or on mud. C. H. Waldron in 1910. 
Polygonum emersum (Michx.) Britton. *LONG-ROOTED SMARTWEED. 
Sloughs, riverbanks, low fields. Common. July 5. 
Polygonum lapathifolium . | DOCK-LEAVED SMARTWEED. 
Fields, roadsides, and low places. Common. July 15. 
Polygonum pennsylvanicum LL. 
Riverbank and low roadsides. Occasional. July 20. 
Polygonum persicaria \. LADIES’ THUMB. 
Riverbank or ditches. Occasional. July 30. 
Polygonum convolvulus \. WILD BUCKWHEAT. 
Fields and roadsides. Common. June 25. 
